JCS: "If North Crosses MDL, Response Based on Southernmost Line When Military Map and UNC Reference Differ"

The Joint Chiefs of Staff have issued guidance to frontline units instructing them to respond to North Korean military incursions across the Military Demarcation Line (MDL) based on the southernmost line, in cases where the South Korean military map and the United Nations Command's MDL reference line differ.

On December 22, the Joint Chiefs of Staff stated, "When North Korean military violations of the Armistice Agreement occur in the Demilitarized Zone, our forces prioritize the 'identified MDL markers' on site to ensure a firm response by field units and to prevent accidental clashes between South and North Korea. However, in areas where MDL markers are not identifiable, we take comprehensive measures by considering both the MDL on military maps and the coordinates of the United Nations Command's MDL markers."

In other words, if North Korean forces cross the MDL according to the South Korean military map but not according to the United Nations Command's reference line, the latter is used as the standard for response. Conversely, if the United Nations Command's reference line is crossed but the line on the South Korean military map is not, the latter is used as the standard for response.

The MDL is the armistice line established through the Korean War Armistice Agreement. After the agreement was signed in 1953, the Military Armistice Commission installed approximately 1,292 concrete markers, each about one meter high, along the MDL. Over time, the number of markers identified by the South Korean side has dwindled to about 200, roughly one-sixth of the total. It is reported that discrepancies between the military map and the United Nations Command's reference line can reach several dozen meters depending on the region.

Incursions by North Korean forces across the MDL have become more frequent since the North began border demarcation work in the DMZ area in April. This year alone, there have been a total of 16 MDL violations, with 10 occurring just last month. The South Korean military responds to such incursions by North Korean forces with warning broadcasts and warning shots.

In September, the South Korean military distributed an official document to frontline units outlining the changes to the MDL violation criteria. However, according to military officials, these measures had already been effectively implemented on the ground since the second half of last year, even before the official document was disseminated.

Meanwhile, last month, the South Korean military proposed inter-Korean military talks to the North to discuss the MDL reference line. The North has shown no particular response to this proposal. On this matter, Defense Ministry spokesperson Jeong Bitna stated at a regular briefing, "As far as I know, there has been no response yet."